斯巴鲁关于四驱技术的官方说明-ACT-4，应该没什么争议了吧

斯巴鲁关于四驱技术的官方说明：

来自斯巴鲁全球网站

网址：www.subaru-global.com

3个问题：

Question 1：

What makes Subaru Symmetrical full-time All-Wheel Drive better than other AWD or 4WD systems? 

是什么让斯巴鲁的对称全时全轮驱动系统比其他AWD系统或4WD系统更好？

链接：http://www.subaru-global.com/news2008n000858.html

译注：资料提供时间为2008年。

The goal of any all-wheel drive (AWD) or four-wheel drive (4WD) system is to improve traction. Good traction is vital for stable acceleration, cornering, and stopping.

Subaru’s Symmetrical full-time All-Wheel Drive continuously powers all four wheels, doubling the traction. Contrast this with 4WD systems that must use two-wheel drive (2WD) mode on-road, where SUVs actually spend most of their time. Or part-time AWD systems that only switch from 2WD mode after detecting wheel slippage and only at low speeds.

In addition, bolting AWD components to an existing 2WD system can help take advantage of available traction, but also adds weight and reduces stability.

任何全轮驱动（AWD）或四轮驱动（4WD）系统的目标是提高牵引力（译注：可理解为驱动力，轮胎三”T”指标之一）。良好的牵引力（译注：可理解为驱动力）对于稳定加速、转弯、和停止（译注：刹车）都是是至关重要的。

斯巴鲁的对称全时全轮驱动（AWD）连续给予全部四个车轮动力，使牵引力（抓地力）倍增。与此形成鲜明对比是，4WD的四驱系统在铺装道路上，必须使用两轮驱动（2WD）模式的，而SUV实际上大部分时间都是行驶在铺装道路上。而分时的全轮驱动系统（AWD）只在较低的速度且检测到车轮打滑时，才从2WD模式切换到AWD模式。

此外，对于运行中的2WD系统，联通AWD组件（译注：系统）有利于增强牵引力（译注：可理解为驱动力），但同时增加了重量且降低稳定性。

Question 2：

Electronically-controlled Multi-Plate Transfer Clutch

电控多片离合器传递

链接：http://www.subaru-global.com/news2008n000858.html

译注：资料提供为2008年。

Subaru uses a Multi-plate Transfer Clutch System (MPT) on many of its automatic-equipped models for a combination of optimum traction and fuel economy. The system uses an electro-mechanical centre differential. Its control unit constantly monitors input from the Throttle Position Sensor (TPS), the Engine Control Module (ECM), the Transmission Control Module (TCM) and wheel speed sensors to provide the most effective front/rear balance of torque. 

In good traction, the MPT’s predetermined logic splits torque 60/40 front/rear for enhanced fuel economy. In poor traction situations or under hard acceleration it can vary the balance up to a full 50/50 for maximum traction.

斯巴鲁为同时获得最佳的牵引和燃油经济性在其很多配备了自动变速箱车型上使用了多片离合器传递系统（MPT）。该系统采用机电中心差分（译注：中央差速器）。控制单元不断监测节气门位置传感器（TPS），发动机控制模块（ECM），变速箱控制模块（TCM）和轮速传感器等信号输入，来提供最有效的前/后力矩平衡。

在良好的牵引力（译注：可理解为抓地力），MPT为提高燃油经济性会按照预定逻辑60 / 40分配前/后的扭矩。在牵引力（译注：可理解为抓地力）不足的情况下或加速困难时，为最大化牵引力（译注：可理解为驱动力）它可以改变扭矩分配到完全50/ 50。

Question 3：

Active torque split AWD

主动扭矩分配AWD

链接：http://www.subaru-global.com/tec_awd.html

译注：资料为现时。

An AWD system developed exclusively for 4-speed automatic transmission, E-4AT (with manual mode) and Lineartronic models to maximise the reliable driving performance of AWD models under any driving conditions. The Lineartronic CVT (Continuous Variable Transmission) uses a chain instead of a belt—allowing a greater span of overall ratios for improved performance and efficiency as well as a faster response to throttle input. The active torque-split AWD system usually distributes torque 60:40 front and rear, however sensors constantly monitor the vehicle"s condition in areas such as changes in grip of the front and rear tyres or vehicle speed. The electronically controlled MP-T (Multi Plate Transfer) adjusts torque distribution to the front and rear tyres in real-time to suit driving conditions, as well as the transmission and driver inputs. This further increases the stability of the AWD system to deliver a safe and agile driving experience.

一个专为4速自动变速器、E-4AT（含手动模式）和Lineartronic各型号变速箱开发的AWD系统，最大化了在任何驾驶条件下的AWD多模式的可靠驱动性能。Lineartronic CVT（无级变速器）使用一个链条而不是钢带，拥有更大的变速比，提升了性能和传动效率，同时油门响应更快。主动扭矩分配AWD系统通常分配到前后轮扭矩比例为60:40，但是传感器不断监测车辆的工况变化，例如前后轮胎抓地力和速度的变化。电控MP-T（多片离合传递）实时调整到前后轮胎扭矩分配来适应驾驶条件、变速箱和驾驶者的操作。这进一步增强了全轮驱动系统的稳定性，提供了一个安全和敏捷的驾驶感受。

另：

国内一种说法是70/30，出处是对富士重工株式会社北京事务所代表长野永的专访，答复称目前是70/30，极限工况50/50。

国外网站上没有查到70/30的说法，只有60/40、调整50/50及对其怀疑的说法。

国外网友也对斯巴鲁的扭矩分配很有兴趣，讨论很多。比如斯巴鲁森林人车主论坛（Subaru forester owner forum）、还有www.subaruforester.org等。

我的另外一个帖子，关于斯巴鲁的四驱结构及宝马的Xdrive结构简介

http://club.autohome.com.cn/bbs/thread-c-285-31281687-1.html

PS：个人翻译，未免有错，敬请指正。